[Federal Register Volume 64, Number 241 (Thursday, December 16, 1999)]
[Rules and Regulations]
[Pages 70181-70184]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-32584]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NM-328-AD; Amendment 39-11473; AD 99-23-22 R1]
RIN 2120-AA64
Airworthiness Directives; Various Transport Category Airplanes
Equipped With Mode ``C'' Transponder(s) With Single Gillham Code
Altitude Input
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment revises an existing airworthiness directive
(AD), applicable to various transport category airplanes equipped with
certain Mode ``C'' transponder(s) with single Gillham code altitude
input. That AD currently requires repetitive tests to detect
discrepancies of the Mode ``C'' transponder(s), air data computer, and
certain wiring connections; and corrective actions, if necessary. The
existing AD is prompted by reports that, during level flight, the
Traffic Alert Collision Avoidance System (TCAS II) issued false
advisories that directed the flightcrew to change course and either
climb or descend. The actions specified by that AD are intended to
prevent such false advisories due to inaccurate airplane altitude
reporting, which could result in the flightcrew deviating the airplane
from its assigned flight path and a possible mid-air collision. This
new action revises certain compliance times and limits the
applicability of the existing AD.
DATES: Effective November 29, 1999.
Comments for inclusion in the Rules Docket must be received on or
before February 14, 2000.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 99-NM-328-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
Information pertaining to this amendment may be obtained from or
examined at the FAA, Transport Airplane Directorate, 1601 Lind Ave,
SW., Renton, Washington 98055-4056.
FOR FURTHER INFORMATION CONTACT: Peter Skaves, Aerospace Engineer,
Airplane and Flight Crew Interface Branch, ANM-111, FAA, Transport
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington
[[Page 70182]]
98055-4056; telephone (425) 227-2795; fax (425) 227-1320.
SUPPLEMENTARY INFORMATION: On November 4, 1999, the FAA issued AD 99-
23-22, amendment 39-11418 (64 FR 61493, November 12, 1999), applicable
to various transport category airplanes equipped with certain Mode
``C'' transponder(s) with single Gillham code altitude input. That AD
requires repetitive tests to detect discrepancies of the Mode ``C''
transponder(s), air data computer, and certain wiring connections; and
corrective actions, if necessary. That action was prompted by reports
that, during level flight, the Traffic Alert Collision Avoidance System
(TCAS II) issued false advisories that directed the flightcrew to
change course and either climb or descend. The actions required by that
AD are intended to prevent such false advisories due to inaccurate
airplane altitude reporting, which could result in the flightcrew
deviating the airplane from its assigned flight path and a possible
mid-air collision.
Actions Since Issuance of Previous Rule
Since the issuance of AD 99-23-22, the FAA has determined that the
existing AD should be revised as follows:
1. The applicability section of the existing AD has been revised to
identify only airplane models used in the same type of operations as
those involved in the reported incidents of reduced airplane
separation. Specifically, the applicable airplane models have been
limited to only those transport category airplanes that can be operated
for extended periods in level flight cruise at altitudes greater than
24,000 feet and that are equipped with Mode ``C'' transponder(s) with
single Gillham code altitude input. As the FAA has not yet determined
the precise cause of the erroneous Mode ``C'' altitude reporting,
investigations into the cause of the unsafe condition are continuing.
The FAA has determined that the applicability of the existing AD should
be limited to airplanes with more exposure to the potential risks of
incorrect altitude reporting. Based on the review of the data received
from these airplane inspections, the FAA may consider future rulemaking
to expand the applicability of this AD.
2. A note has been added to the existing AD to clarify that the
requirements of that AD DO NOT supersede the current airplane Master
Minimum Equipment List (MMEL) requirements for deferral of repair of
malfunctioning systems. The existing AD states that any malfunctioning
Mode ``C'' altitude reporting system is to be repaired prior to further
flight. Note 3 of this revised AD explains that Mode ``C'' transponder
altitude reporting systems that have been determined to be
malfunctioning must be turned off and placarded as inoperative, as
specified in the MMEL. The airplane may then be operated in accordance
with the MMEL.
3. The compliance time for accomplishment of the initial and
repetitive tests required by paragraph (a) of the existing AD has been
extended from 45 days to 90 days after the effective date of the
existing AD. Test results received to date indicate that a substantial
number of airplanes have already been tested without failures. Based on
these test results and on the increased awareness of operators using
Mode ``C'' altitude reporting, the FAA has determined that the risk of
exposure to incorrect altitude reporting has been sufficiently reduced
to allow extension of the compliance time for accomplishment of the
initial and repetitive testing. Extended test intervals also will
provide additional time for operators required to schedule and execute
the tests. In addition, the reporting requirement specified in
paragraph (c) of the existing AD has been extended from 10 days to 20
days after accomplishment of the initial and repetitive tests required
by paragraph (a) of the existing AD.
4. The alternative method of compliance paragraph of the existing
AD has been revised to identify the Manager, Airplane and Flight Crew
Interface Branch, Transport Airplane Directorate, as the point of
contact in lieu of the Manager, Seattle Aircraft Certification Office.
Explanation of Requirements of Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of this same type design, this AD
revises AD 99-23-22 to continue to require repetitive tests to detect
discrepancies of the Mode ``C'' transponder(s), air data computer, and
certain wiring connections; and corrective actions, if necessary. This
action revises certain compliance times and limits the applicability of
the existing AD. This AD also includes a note which describes
provisions for continued operation of the airplane in accordance with
the provisions and limitations specified in the operator's FAA-approved
Master Minimum Equipment List (MMEL).
Interim Action
This is considered to be interim action until final action is
identified, at which time the FAA may consider further rulemaking.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications shall identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the rule. All comments submitted will be
available, both before and after the closing date for comments, in the
Rules Docket for examination by interested persons. A report that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 99-NM-328-AD.'' The postcard will be date stamped and
returned to the commenter.
Regulatory Impact
The regulations adopted herein will not have a substantial direct
effect on the States, on the relationship between the national
Government and the States, or on the distribution of power and
responsibilities among the various levels of government. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
The FAA has determined that this regulation is an emergency
regulation
[[Page 70183]]
that must be issued immediately to correct an unsafe condition in
aircraft, and that it is not a ``significant regulatory action'' under
Executive Order 12866. It has been determined further that this action
involves an emergency regulation under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979). If it is determined that
this emergency regulation otherwise would be significant under DOT
Regulatory Policies and Procedures, a final regulatory evaluation will
be prepared and placed in the Rules Docket. A copy of it, if filed, may
be obtained from the Rules Docket at the location provided under the
caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends part 39 of
the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-11418 (64 FR
61493, November 12, 1999), and by adding a new airworthiness directive
(AD), amendment 39-11473, to read as follows:
099-23-22 R1 Transport Category Airplanes: Amendment 39-11473.
Docket 99-NM-328-AD. Revises AD 99-23-22, Amendment 39-11418.
Applicability: Transport category airplanes, as listed below,
certificated in any category, equipped with any Mode ``C''
transponder with single Gillham code altitude input, including, but
not limited to, the transponder part numbers listed below. Whether a
Mode ``C'' transponder has a single Gillham code altitude input may
be determined by reviewing the transponder installation
instructions.
Airplane Models
Airbus Industrie
A300
A310
British Aerospace
BAe Avro 146-RJ
BAe ATP
Fokker
F28 Mark 0070
F28 Mark 0100
F28 Mark 1000-4000
Lockheed
L-1011 TriStar
L-188 Electra
CASA
CN-235
Dassault Aviation
Mystere Falcon 50
Mystere Falcon 900
Mystere Falcon 200
Fan Jet Falcon Series G
Boeing (MDC)
DC-10-30
DC-10-40
DC-9
DC-9-81
DC-9-82
DC-9-83
DC-9-87
Boeing 707
Boeing 727
Boeing 737
Boeing 747
Bombardier
CL-215-1A10
CL-215-6B11
CL-600-1A11
CL-600-2A12
CL-600-2B16
Gulfstream
G1159 (G-II)
G-1159A (G-III)
G-IV
Mode ``C'' Transponder Part Numbers:
Rockwell Collins
622-2224-001
622-2224-003
522-2703-001
522-2703-011
787-6211-001
787-6211-002
Bendix
066-1056-00
066-1056-01
066-1123-00
2041599-6508
Wilcox
97637-201
97637-301
IFF
APX-100
APX-101
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must request approval for an
alternative method of compliance in accordance with paragraph (d) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and, if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To prevent false Traffic Alert Collision Avoidance System (TCAS
II) advisories due to inaccurate airplane altitude reporting, which
could result in the flightcrew deviating the airplane from its
assigned flight path and a possible mid-air collision, accomplish
the following:
Repetitive Tests
(a) Within 90 days after November 29, 1999 (the effective date
of AD 99-23-22, amendment 39-11418): Perform the test procedures
specified in paragraphs (a)(1) through (a)(9) of this AD to detect
any discrepancies of the Mode ``C'' transponder(s), air data
computer (ADC), or Gillham wiring connections, in accordance with
the applicable ADC and Mode ``C'' transponder component maintenance
manuals and airplane maintenance manual. Repeat the test procedures
thereafter at intervals not to exceed 90 days.
(1) Connect an air data test set to the Captain's (No. 1) Pitot/
Static system.
(2) In the airplane flight deck, select Mode ``C'' transponder
(1), or left Mode ``C'' transponder, depending on airplane flight
deck configuration, and select ADC source (1).
(3) Select the air data test set to the following altitude
reporting values:
1,000 feet;
4,100 feet;
15,700 feet; and
31,000 feet.
(4) For each selected altitude, verify that the Mode ``C''
altitude reporting is within tolerance (+/-125 feet), and record the
altitude output as follows:
1,000 feet (+/-125 feet);
4,100 feet (+/-125 feet);
15,700 (+/-125 feet); and
31,000 feet (+/-125 feet).
(5) In the airplane flight deck, select ADC source (2) and
repeat paragraphs (a)(3) and (a)(4) of this AD.
(6) In the airplane flight deck, select Mode ``C'' transponder
(2), or the right Mode ``C'' transponder, depending on airplane
flight deck configuration, select ADC source (1), and repeat
paragraphs (a)(3) and (a)(4) of this AD.
(7) In the airplane flight deck, select ADC source (2) and
repeat paragraphs (a)(3) and (a)(4) of this AD.
(8) Connect an air data test set to the Captain's (No. 2) Pitot/
Static system.
(9) Repeat paragraphs (a)(2) through (a)(7) of this AD.
Note 2: The tests required by paragraph (a) of this AD examine
the three primary sources of inaccurate airplane altitude reporting.
These three sources are: ADC's, Mode ``C'' transponders, and the
Gillham wiring connections between the ADC and Mode ``C''
transponder.
Corrective Actions
(b) Except as permitted by the Master Minimum Equipment List
(MMEL): If any discrepancy is detected during any test required by
paragraph (a) of this AD: Prior to further flight, repair in
accordance with the applicable ADC and Mode ``C'' transponder
component maintenance manual and airplane maintenance manual. If the
repair information is not available in the applicable manual, except
as permitted by the MMEL, prior to further flight, repair in
accordance with a method approved by the Manager, Seattle Aircraft
Certification Office (ACO), FAA, Transport Airplane Directorate.
Note 3: The airplane may be operated in accordance with the
provisions and
[[Page 70184]]
limitations specified in the FAA-approved MMEL, provided that only
one Mode ``C'' transponder on the airplane is inoperative.
Reporting Requirement
(c) Within 20 days after accomplishing the initial and
repetitive tests required by paragraph (a) of this AD, submit a
report of the inspection and test results (both positive and
negative findings) to: Peter Skaves, Aerospace Engineer, Airplane
and Flight Crew Interface Branch, ANM-111, FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056;
fax (425) 227-1320. The test results must include the Mode ``C''
transponder(s) and ADC part number(s), and must specify if any
discrepancies of the Gillham wiring connections were detected, and
if corrective action was required. Information collection
requirements contained in this regulation have been approved by the
Office of Management and Budget (OMB) under the provisions of the
Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have
been assigned OMB Control Number 2120-0056.
Alternative Methods of Compliance
(d) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Airplane and Flight Crew Interface
Branch, ANM-111, FAA, Transport Airplane Directorate. Operators
shall submit their requests through an appropriate FAA Principal
Maintenance or Avionics Inspector, who may add comments and then
send it to the Manager, ANM-111.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Manager, ANM-111.
Special Flight Permits
(e) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be accomplished.
(f) The effective date of this amendment remains November 29,
1999.
Issued in Renton, Washington, on December 10, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-32584 Filed 12-15-99; 8:45 am]
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